Hi!
You could use Mia_material_x (Maya) or Arch&Design shader (3ds Max) to make your textures realistic. After you do this, plug a mia_rouncorners in the “overall bump” of your mia_x textures, so the edges of your objects will look softer, more realistic.
For the gold material, use mia_material_x too. You can choose from a preset (chrome, stained metal) or recreate the gold yourself, but keep your glossy samples under 32/64…
In mental ray Render Settings:
-
Quality Tab/Raytracing:
keep reflections / refractions to 2 / 2 and Max Trace Depth at 4
-
Indirect Lighting: use Final Gathering (You don’t need Global Illumination for outdoor…)
set Accuracy to 50-100 and point density to 0.1-0.4
You should delete your Physical Sun and Sky, and create a new one if you have added too much samples values. And set your Anti-Aliasing to Min 0 Max 2.
Participating Media (particles in the air) is complicated, you need to find a good tutorial and follow step-by-step…
You can simulate a foggy day lighting by adding haze in the skylight. I hope it helps!